The discussion below is merely provided for general background information and is not intended to be used as an aid in determining the scope of the claimed subject matter.
FIG. 1 schematically illustrates a wind turbine assembly 10 and a hub coordinate system used to define forces and moments experienced by the wind turbine assembly 10. The wind turbine assembly 10 will be subjected to various loads (forces and moments) when in operation, for example but not limited to a difference in wind speeds from wind above the wind turbine assembly and wind closer to the ground/water surface as well as various forms of wind gusts. The forces and moments can be defined with respect to three orthogonal axes (X, Y and Z) as an axial force FX, radial forces FY, FZ, shaft torque MX, and moments about radial axes orthogonal to the shaft axis, i.e. MY, MZ. These loads typically are of different magnitudes and different frequencies, but are applied simultaneously to the wind turbine assembly 10.